To facilitate wireless communications, the Institute of Electrical and Electronics Engineers (IEEE) has promulgated a number of wireless standards. These include the 802.11 (WiFi) standards and the 802.16 (WiMAX) standards. Likewise, the International Telecommunication Union (ITU) has promulgated standards to facilitate wireless communications. This includes TIA-856, which is also known as Evolution-Data Optimized (EV-DO). The European Telecommunications Standards Institute (ETSI) has also promulgated a standard known as long term evolution (LTE). Additional standards such as the fifth generation communication system (5G) are also being pursued. These standards pursue the aim of providing a comprehensive IP solution where voice, data, and streamed multimedia can be given to users on an “anytime, anywhere” basis. These standards also aim to provide higher data rates than previous generations. All of these standards may include specifications for various aspects of wireless communication with a network. These aspects include processes for registering on the network, carrier modulation, frequency bands of operation, and message formats.
Transmit beamforming uses multiple antennas to control the direction of a transmission by appropriately weighting the magnitude and phase of the signals sent to individual antennas. Receive beamforming appropriately amplifies (i.e., weights) and delays (i.e., adjusts phase) the signals from each antenna. Different weighting patterns (e.g., Dolph-Chebyshev) can be used to achieve desired sensitivity patterns. Typically, a main lobe is produced together with nulls and sidelobes. As well as controlling the main lobe width (the beam) and the sidelobe levels, the position (i.e., angle) of a null and the main lobe can be controlled. This is useful to increase sensitivity in one particular direction, while decreasing sensitivity to interference from other directions. A similar result can be obtained on transmission. These beam steering techniques can help provide better coverage to specific areas near the edges of wireless coverage.
Another technique to improve wireless coverage is transmit time interval (TTI) bundling. When activated, TTI bundling configures a user equipment (UE) device to send the same transport block, but with different error detection and correction information, in multiple consecutive transmit time intervals. This redundant transmission of transport blocks can effectively improve coverage by up to 4 dB.
Overview
In an embodiment, a method of operating a communication system, includes determining whether a first sector of an access node is using beamforming to receive communication from a wireless device. Whether a first angle of a first main beamforming lobe being used by the first sector to receive communication from the wireless device meets a first threshold criteria is determined. Whether a second sector of the access node is using beamforming to receive communication is determined. Whether a second angle of a second main beamforming lobe being used by the second sector to receive communication meets a second threshold criteria is determined. Based on at least one of whether the first sector of an access node is using beamforming to receive communication from the wireless device, whether the first threshold criteria is met, whether the second sector of the access node is using beamforming to receive communication, and whether the second threshold criteria is met, it is determined whether to use TTI bundling to communicate with the wireless device.
In an embodiment, a communication system includes a first sector of an access node, a second sector of the access node, and a processing node. The first sector can use beamforming to receive communication from a wireless device. The second sector of the access node can use beamforming to receive communication. The processing node determines whether a first sector of an access node is using beamforming to receive communication from a wireless device. The processing node determines whether a first angle of a first main beamforming lobe being used by the first sector to receive communication from the wireless device meets a first threshold criteria. The processing node determines whether a second sector of the access node is using beamforming to receive communication. The processing node determines whether a second angle of a second main beamforming lobe being used by the second sector to receive communication meets a second threshold criteria. Based on at least one of whether the first sector of an access node is using beamforming to receive communication from the wireless device, whether the first threshold criteria is met, whether the second sector of the access node is using beamforming to receive communication, and whether the second threshold criteria is met, the processing node determines whether to use TTI bundling to communicate with the wireless device.
In an embodiment, a method of operating a communication system includes receiving, at a first sector of an access node, communication from a wireless device using beamforming by the first sector. At a second sector of the access node, communication from at least one additional wireless device is received using beamforming by the second sector. Based on the first sector using beamforming to receive communication from the wireless device, and based on the second sector using beamforming to receive communication from the at least one additional wireless device, and based on a first angle of a first main beamforming lobe being used by the first sector to receive communication from the wireless device meeting a first threshold criteria, a TTI bundling size is selected to be used by the first sector for communication from the wireless device.